Previous studies have shown that mannosylated bovine serum albumin (mBSA) enhances the respiratory burst (RB), phagocytosis, and killing of Candida albicans and Escherichia coli by resident murine peritoneal macrophages (Mphi). Upregulation of the above Mphi functions was associated with the binding of mBSA to the macrophage mannose receptor. The present study was done to determine if certain glyconutrients could stimulate Mphi functions in a similar manner. Resident peritoneal murine Mphi collected from C57BL/6 mice were exposed to the glyconutrients for 10 and 60 min. The RB was measured using chemiluminescence. Both phagocytosis and killing were measured after incubation with each of the following microorganisms: Candida albicans, Escherichia coli and Staphylococcus aureus. The percent phagocytosis and killing were determined using fluorescence microscopy. Results indicated that certain glyconutrients, caused a dose and time dependent effect on Mphi-induced killing of all three microorganisms.